Convert Atlas to infinite lazy growth

The atlas will now expand as needed for any query, but only initialise the chunk tile memory when requested

	While this may still be a pre-mature optimisation, it does simplify some code and ensures that our memory footprint stays small, for the most part

cmd/rove-server/internal/server.go

@@ -83,6 +83,7 @@ func NewServer(opts ...ServerOption) *Server {
 		address:     "",
 		persistence: EphemeralData,
 		schedule:    cron.New(),
+		world:       game.NewWorld(16),
 	}
 
 	// Apply all options
@@ -90,9 +91,6 @@ func NewServer(opts ...ServerOption) *Server {
 		o(s)
 	}
 
-	// Start small, we can grow the world later
-	s.world = game.NewWorld(4, 8)
-
 	return s
 }
 
@@ -114,11 +112,6 @@ func (s *Server) Initialise(fillWorld bool) (err error) {
 	}
 	s.accountant = accounts.NewAccountantClient(s.clientConn)
 
-	// Spawn a border on the default world
-	if err := s.world.SpawnWorld(fillWorld); err != nil {
-		return err
-	}
-
 	// Load the world file
 	if err := s.LoadWorld(); err != nil {
 		return err

pkg/atlas/atlas.go

@@ -1,7 +1,6 @@
 package atlas
 
 import (
-	"fmt"
 	"log"
 	"math/rand"
 
@@ -16,114 +15,98 @@ type Chunk struct {
 	Tiles []byte `json:"tiles"`
 }
 
+// SpawnContent will create a chunk and fill it with spawned tiles
+func (c *Chunk) SpawnContent(size int) {
+	c.Tiles = make([]byte, size*size)
+	for i := 0; i < len(c.Tiles); i++ {
+		c.Tiles[i] = objects.Empty
+	}
+
+	// For now, fill it randomly with objects
+	for i := range c.Tiles {
+		if rand.Intn(16) == 0 {
+			c.Tiles[i] = objects.LargeRock
+		} else if rand.Intn(32) == 0 {
+			c.Tiles[i] = objects.SmallRock
+		}
+	}
+}
+
 // Atlas represents a grid of Chunks
 type Atlas struct {
 	// Chunks represents all chunks in the world
 	// This is intentionally not a 2D array so it can be expanded in all directions
 	Chunks []Chunk `json:"chunks"`
 
-	// size is the current width/height of the given atlas
+	// CurrentSize is the current width/height of the given atlas
-	Size int `json:"size"`
+	CurrentSize int `json:"currentSize"`
 
 	// ChunkSize is the dimensions of each chunk
 	ChunkSize int `json:"chunksize"`
 }
 
 // NewAtlas creates a new empty atlas
-func NewAtlas(size, chunkSize int) Atlas {
+func NewAtlas(chunkSize int) Atlas {
-	if size%2 != 0 {
+	return Atlas{
-		log.Fatal("atlas size must always be even")
+		CurrentSize: 0,
+		Chunks:      nil,
+		ChunkSize:   chunkSize,
 	}
-
-	a := Atlas{
-		Size:      size,
-		Chunks:    make([]Chunk, size*size),
-		ChunkSize: chunkSize,
-	}
-
-	// Initialise all the chunks
-	for i := range a.Chunks {
-		tiles := make([]byte, chunkSize*chunkSize)
-		for i := 0; i < len(tiles); i++ {
-			tiles[i] = objects.Empty
-		}
-		a.Chunks[i] = Chunk{
-			Tiles: tiles,
-		}
-	}
-
-	return a
-}
-
-// SpawnRocks peppers the world with rocks
-func (a *Atlas) SpawnRocks() error {
-	extent := a.ChunkSize * (a.Size / 2)
-
-	// Pepper the current world with rocks
-	for i := -extent; i < extent; i++ {
-		for j := -extent; j < extent; j++ {
-			if rand.Intn(16) == 0 {
-				if err := a.SetTile(vector.Vector{X: i, Y: j}, objects.SmallRock); err != nil {
-					return err
-				}
-			}
-		}
-	}
-
-	return nil
-}
-
-// SpawnWalls spawns the around the world
-func (a *Atlas) SpawnWalls() error {
-	extent := a.ChunkSize * (a.Size / 2)
-
-	// Surround the atlas in walls
-	for i := -extent; i < extent; i++ {
-
-		if err := a.SetTile(vector.Vector{X: i, Y: extent - 1}, objects.LargeRock); err != nil { // N
-			return err
-		} else if err := a.SetTile(vector.Vector{X: extent - 1, Y: i}, objects.LargeRock); err != nil { // E
-			return err
-		} else if err := a.SetTile(vector.Vector{X: i, Y: -extent}, objects.LargeRock); err != nil { // S
-			return err
-		} else if err := a.SetTile(vector.Vector{X: -extent, Y: i}, objects.LargeRock); err != nil { // W
-			return err
-		}
-	}
-
-	return nil
 }
 
 // SetTile sets an individual tile's kind
-func (a *Atlas) SetTile(v vector.Vector, tile byte) error {
+func (a *Atlas) SetTile(v vector.Vector, tile byte) {
-	chunk := a.toChunk(v)
+	// Get the chunk, expand, and spawn it if needed
-	if chunk >= len(a.Chunks) {
+	c := a.toChunkWithGrow(v)
-		return fmt.Errorf("location outside of allocated atlas")
+	chunk := a.Chunks[c]
+	if chunk.Tiles == nil {
+		chunk.SpawnContent(a.ChunkSize)
 	}
 
 	local := a.toChunkLocal(v)
 	tileId := local.X + local.Y*a.ChunkSize
-	if tileId >= len(a.Chunks[chunk].Tiles) {
+
-		return fmt.Errorf("location outside of allocated chunk")
+	// Sanity check
+	if tileId >= len(chunk.Tiles) || tileId < 0 {
+		log.Fatalf("Local tileID is not in valid chunk, somehow, this means something is very wrong")
 	}
-	a.Chunks[chunk].Tiles[tileId] = tile
+
-	return nil
+	// Set the chunk back
+	chunk.Tiles[tileId] = tile
+	a.Chunks[c] = chunk
 }
 
 // GetTile will return an individual tile
-func (a *Atlas) GetTile(v vector.Vector) (byte, error) {
+func (a *Atlas) GetTile(v vector.Vector) byte {
-	chunk := a.toChunk(v)
+	// Get the chunk, expand, and spawn it if needed
-	if chunk >= len(a.Chunks) {
+	c := a.toChunkWithGrow(v)
-		return 0, fmt.Errorf("location outside of allocated atlas")
+	chunk := a.Chunks[c]
+	if chunk.Tiles == nil {
+		chunk.SpawnContent(a.ChunkSize)
 	}
 
 	local := a.toChunkLocal(v)
 	tileId := local.X + local.Y*a.ChunkSize
-	if tileId >= len(a.Chunks[chunk].Tiles) {
+
-		return 0, fmt.Errorf("location outside of allocated chunk")
+	// Sanity check
+	if tileId >= len(chunk.Tiles) || tileId < 0 {
+		log.Fatalf("Local tileID is not in valid chunk, somehow, this means something is very wrong")
 	}
 
-	return a.Chunks[chunk].Tiles[tileId], nil
+	return chunk.Tiles[tileId]
+}
+
+// toChunkWithGrow will expand the atlas for a given tile, returns the new chunk
+func (a *Atlas) toChunkWithGrow(v vector.Vector) int {
+	for {
+		// Get the chunk, and grow looping until we have a valid chunk
+		chunk := a.toChunk(v)
+		if chunk >= len(a.Chunks) || chunk < 0 {
+			a.grow()
+		} else {
+			return chunk
+		}
+	}
 }
 
 // toChunkLocal gets a chunk local coordinate for a tile
@@ -131,7 +114,7 @@ func (a *Atlas) toChunkLocal(v vector.Vector) vector.Vector {
 	return vector.Vector{X: maths.Pmod(v.X, a.ChunkSize), Y: maths.Pmod(v.Y, a.ChunkSize)}
 }
 
-// GetChunkID gets the chunk ID for a position in the world
+// GetChunkID gets the current chunk ID for a position in the world
 func (a *Atlas) toChunk(v vector.Vector) int {
 	local := a.toChunkLocal(v)
 	// Get the chunk origin itself
@@ -139,50 +122,34 @@ func (a *Atlas) toChunk(v vector.Vector) int {
 	// Divided it by the number of chunks
 	origin = origin.Divided(a.ChunkSize)
 	// Shift it by our size (our origin is in the middle)
-	origin = origin.Added(vector.Vector{X: a.Size / 2, Y: a.Size / 2})
+	origin = origin.Added(vector.Vector{X: a.CurrentSize / 2, Y: a.CurrentSize / 2})
 	// Get the ID based on the final values
-	return (a.Size * origin.Y) + origin.X
+	return (a.CurrentSize * origin.Y) + origin.X
 }
 
 // chunkOrigin gets the chunk origin for a given chunk index
 func (a *Atlas) chunkOrigin(chunk int) vector.Vector {
 	v := vector.Vector{
-		X: maths.Pmod(chunk, a.Size) - (a.Size / 2),
+		X: maths.Pmod(chunk, a.CurrentSize) - (a.CurrentSize / 2),
-		Y: (chunk / a.Size) - (a.Size / 2),
+		Y: (chunk / a.CurrentSize) - (a.CurrentSize / 2),
 	}
 
 	return v.Multiplied(a.ChunkSize)
 }
 
-// GetWorldExtent gets the min and max valid coordinates of world
+// grow will expand the current atlas in all directions by one chunk
-func (a *Atlas) GetWorldExtents() (min, max vector.Vector) {
+func (a *Atlas) grow() error {
-	min = vector.Vector{
-		X: -(a.Size / 2) * a.ChunkSize,
-		Y: -(a.Size / 2) * a.ChunkSize,
-	}
-	max = vector.Vector{
-		X: -min.X - 1,
-		Y: -min.Y - 1,
-	}
-	return
-}
-
-// Grow will return a grown copy of the current atlas
-func (a *Atlas) Grow(size int) error {
-	if size%2 != 0 {
-		return fmt.Errorf("atlas size must always be even")
-	}
-	delta := size - a.Size
-	if delta < 0 {
-		return fmt.Errorf("cannot shrink an atlas")
-	} else if delta == 0 {
-		return nil
-	}
-
 	// Create a new atlas
-	newAtlas := NewAtlas(size, a.ChunkSize)
+	newAtlas := NewAtlas(a.ChunkSize)
 
-	// Copy old chunks into new chunks
+	// Expand by one on each axis
+	newAtlas.CurrentSize = a.CurrentSize + 2
+
+	// Allocate the new atlas chunks
+	// These chunks will have nil tile slices
+	newAtlas.Chunks = make([]Chunk, newAtlas.CurrentSize*newAtlas.CurrentSize)
+
+	// Copy all old chunks into the new atlas
 	for index, chunk := range a.Chunks {
 		// Calculate the new chunk location and copy over the data
 		newAtlas.Chunks[newAtlas.toChunk(a.chunkOrigin(index))] = chunk

pkg/atlas/atlas_test.go

@@ -3,60 +3,63 @@ package atlas
 import (
 	"testing"
 
-	"github.com/mdiluz/rove/pkg/objects"
 	"github.com/mdiluz/rove/pkg/vector"
 	"github.com/stretchr/testify/assert"
 )
 
 func TestAtlas_NewAtlas(t *testing.T) {
-	a := NewAtlas(2, 1)
+	a := NewAtlas(1)
 	assert.NotNil(t, a)
-	// Tiles should look like: 2 | 3
+	assert.Equal(t, 1, a.ChunkSize)
-	//  -----
+	assert.Equal(t, 0, len(a.Chunks)) // Should start empty
-	//  0 | 1
-	assert.Equal(t, 4, len(a.Chunks))
-
-	a = NewAtlas(4, 1)
-	assert.NotNil(t, a)
-	// Tiles should look like: 2 | 3
-	//  -----
-	//  0 | 1
-	assert.Equal(t, 16, len(a.Chunks))
 }
 
 func TestAtlas_toChunk(t *testing.T) {
-	a := NewAtlas(2, 1)
+	a := NewAtlas(1)
 	assert.NotNil(t, a)
-	// Tiles should look like: 2 | 3
+
+	// We start empty so we'll look like this
+	chunkID := a.toChunk(vector.Vector{X: 0, Y: 0})
+	assert.Equal(t, 0, chunkID)
+
+	// Get a tile to spawn the chunks
+	a.GetTile(vector.Vector{})
+
+	// Chunks should look like:
+	//  2 | 3
 	//  -----
 	//  0 | 1
-	tile := a.toChunk(vector.Vector{X: 0, Y: 0})
+	chunkID = a.toChunk(vector.Vector{X: 0, Y: 0})
-	assert.Equal(t, 3, tile)
+	assert.Equal(t, 3, chunkID)
-	tile = a.toChunk(vector.Vector{X: 0, Y: -1})
+	chunkID = a.toChunk(vector.Vector{X: 0, Y: -1})
-	assert.Equal(t, 1, tile)
+	assert.Equal(t, 1, chunkID)
-	tile = a.toChunk(vector.Vector{X: -1, Y: -1})
+	chunkID = a.toChunk(vector.Vector{X: -1, Y: -1})
-	assert.Equal(t, 0, tile)
+	assert.Equal(t, 0, chunkID)
-	tile = a.toChunk(vector.Vector{X: -1, Y: 0})
+	chunkID = a.toChunk(vector.Vector{X: -1, Y: 0})
-	assert.Equal(t, 2, tile)
+	assert.Equal(t, 2, chunkID)
 
-	a = NewAtlas(2, 2)
+	a = NewAtlas(2)
 	assert.NotNil(t, a)
-	// Tiles should look like:
+	// Get a tile to spawn the chunks
+	a.GetTile(vector.Vector{})
+	// Chunks should look like:
 	// 2 | 3
 	// -----
 	// 0 | 1
-	tile = a.toChunk(vector.Vector{X: 1, Y: 1})
+	chunkID = a.toChunk(vector.Vector{X: 1, Y: 1})
-	assert.Equal(t, 3, tile)
+	assert.Equal(t, 3, chunkID)
-	tile = a.toChunk(vector.Vector{X: 1, Y: -2})
+	chunkID = a.toChunk(vector.Vector{X: 1, Y: -2})
-	assert.Equal(t, 1, tile)
+	assert.Equal(t, 1, chunkID)
-	tile = a.toChunk(vector.Vector{X: -2, Y: -2})
+	chunkID = a.toChunk(vector.Vector{X: -2, Y: -2})
-	assert.Equal(t, 0, tile)
+	assert.Equal(t, 0, chunkID)
-	tile = a.toChunk(vector.Vector{X: -2, Y: 1})
+	chunkID = a.toChunk(vector.Vector{X: -2, Y: 1})
-	assert.Equal(t, 2, tile)
+	assert.Equal(t, 2, chunkID)
 
-	a = NewAtlas(4, 2)
+	a = NewAtlas(2)
 	assert.NotNil(t, a)
-	// Tiles should look like:
+	// Get a tile to spawn the chunks
+	a.GetTile(vector.Vector{X: 0, Y: 3})
+	// Chunks should look like:
 	//  12| 13|| 14| 15
 	// ----------------
 	//  8 | 9 || 10| 11
@@ -64,107 +67,58 @@ func TestAtlas_toChunk(t *testing.T) {
 	//  4 | 5 || 6 | 7
 	// ----------------
 	//  0 | 1 || 2 | 3
-	tile = a.toChunk(vector.Vector{X: 1, Y: 3})
+	chunkID = a.toChunk(vector.Vector{X: 1, Y: 3})
-	assert.Equal(t, 14, tile)
+	assert.Equal(t, 14, chunkID)
-	tile = a.toChunk(vector.Vector{X: 1, Y: -3})
+	chunkID = a.toChunk(vector.Vector{X: 1, Y: -3})
-	assert.Equal(t, 2, tile)
+	assert.Equal(t, 2, chunkID)
-	tile = a.toChunk(vector.Vector{X: -1, Y: -1})
+	chunkID = a.toChunk(vector.Vector{X: -1, Y: -1})
-	assert.Equal(t, 5, tile)
+	assert.Equal(t, 5, chunkID)
-	tile = a.toChunk(vector.Vector{X: -2, Y: 2})
+	chunkID = a.toChunk(vector.Vector{X: -2, Y: 2})
-	assert.Equal(t, 13, tile)
+	assert.Equal(t, 13, chunkID)
 }
 
 func TestAtlas_GetSetTile(t *testing.T) {
-	a := NewAtlas(4, 10)
+	a := NewAtlas(10)
 	assert.NotNil(t, a)
 
 	// Set the origin tile to 1 and test it
-	assert.NoError(t, a.SetTile(vector.Vector{X: 0, Y: 0}, 1))
+	a.SetTile(vector.Vector{X: 0, Y: 0}, 1)
-	tile, err := a.GetTile(vector.Vector{X: 0, Y: 0})
+	tile := a.GetTile(vector.Vector{X: 0, Y: 0})
-	assert.NoError(t, err)
 	assert.Equal(t, byte(1), tile)
 
 	// Set another tile to 1 and test it
-	assert.NoError(t, a.SetTile(vector.Vector{X: 5, Y: -2}, 2))
+	a.SetTile(vector.Vector{X: 5, Y: -2}, 2)
-	tile, err = a.GetTile(vector.Vector{X: 5, Y: -2})
+	tile = a.GetTile(vector.Vector{X: 5, Y: -2})
-	assert.NoError(t, err)
 	assert.Equal(t, byte(2), tile)
 }
 
 func TestAtlas_Grown(t *testing.T) {
 	// Start with a small example
-	a := NewAtlas(2, 2)
+	a := NewAtlas(2)
 	assert.NotNil(t, a)
-	assert.Equal(t, 4, len(a.Chunks))
+	assert.Equal(t, 0, len(a.Chunks))
 
 	// Set a few tiles to values
-	assert.NoError(t, a.SetTile(vector.Vector{X: 0, Y: 0}, 1))
+	a.SetTile(vector.Vector{X: 0, Y: 0}, 1)
-	assert.NoError(t, a.SetTile(vector.Vector{X: -1, Y: -1}, 2))
+	a.SetTile(vector.Vector{X: -1, Y: -1}, 2)
-	assert.NoError(t, a.SetTile(vector.Vector{X: 1, Y: -2}, 3))
+	a.SetTile(vector.Vector{X: 1, Y: -2}, 3)
 
-	// Grow once to just double it
+	// Check tile values
-	err := a.Grow(4)
+	tile := a.GetTile(vector.Vector{X: 0, Y: 0})
-	assert.NoError(t, err)
-	assert.Equal(t, 16, len(a.Chunks))
-
-	tile, err := a.GetTile(vector.Vector{X: 0, Y: 0})
-	assert.NoError(t, err)
 	assert.Equal(t, byte(1), tile)
 
-	tile, err = a.GetTile(vector.Vector{X: -1, Y: -1})
+	tile = a.GetTile(vector.Vector{X: -1, Y: -1})
-	assert.NoError(t, err)
 	assert.Equal(t, byte(2), tile)
 
-	tile, err = a.GetTile(vector.Vector{X: 1, Y: -2})
+	tile = a.GetTile(vector.Vector{X: 1, Y: -2})
-	assert.NoError(t, err)
 	assert.Equal(t, byte(3), tile)
 
-	// Grow it again even bigger
+	tile = a.GetTile(vector.Vector{X: 0, Y: 0})
-	err = a.Grow(10)
-	assert.NoError(t, err)
-	assert.Equal(t, 100, len(a.Chunks))
-
-	tile, err = a.GetTile(vector.Vector{X: 0, Y: 0})
-	assert.NoError(t, err)
 	assert.Equal(t, byte(1), tile)
 
-	tile, err = a.GetTile(vector.Vector{X: -1, Y: -1})
+	tile = a.GetTile(vector.Vector{X: -1, Y: -1})
-	assert.NoError(t, err)
 	assert.Equal(t, byte(2), tile)
 
-	tile, err = a.GetTile(vector.Vector{X: 1, Y: -2})
+	tile = a.GetTile(vector.Vector{X: 1, Y: -2})
-	assert.NoError(t, err)
 	assert.Equal(t, byte(3), tile)
 }
-
-func TestAtlas_SpawnWorld(t *testing.T) {
-	// Start with a small example
-	a := NewAtlas(2, 4)
-	assert.NotNil(t, a)
-	assert.Equal(t, 4, len(a.Chunks))
-	assert.NoError(t, a.SpawnWalls())
-
-	for i := -4; i < 4; i++ {
-		tile, err := a.GetTile(vector.Vector{X: i, Y: -4})
-		assert.NoError(t, err)
-		assert.Equal(t, objects.LargeRock, tile)
-	}
-
-	for i := -4; i < 4; i++ {
-		tile, err := a.GetTile(vector.Vector{X: -4, Y: i})
-		assert.NoError(t, err)
-		assert.Equal(t, objects.LargeRock, tile)
-	}
-
-	for i := -4; i < 4; i++ {
-		tile, err := a.GetTile(vector.Vector{X: 3, Y: i})
-		assert.NoError(t, err)
-		assert.Equal(t, objects.LargeRock, tile)
-	}
-
-	for i := -4; i < 4; i++ {
-		tile, err := a.GetTile(vector.Vector{X: i, Y: 3})
-		assert.NoError(t, err)
-		assert.Equal(t, objects.LargeRock, tile)
-	}
-}

pkg/game/command_test.go

@@ -8,7 +8,7 @@ import (
 )
 
 func TestCommand_Move(t *testing.T) {
-	world := NewWorld(2, 8)
+	world := NewWorld(8)
 	a, err := world.SpawnRover()
 	assert.NoError(t, err)
 	pos := vector.Vector{

pkg/game/world.go

@@ -12,7 +12,6 @@ import (
 	"github.com/google/uuid"
 	"github.com/mdiluz/rove/pkg/atlas"
 	"github.com/mdiluz/rove/pkg/bearing"
-	"github.com/mdiluz/rove/pkg/maths"
 	"github.com/mdiluz/rove/pkg/objects"
 	"github.com/mdiluz/rove/pkg/vector"
 )
@@ -44,7 +43,7 @@ type World struct {
 var wordsFile = os.Getenv("WORDS_FILE")
 
 // NewWorld creates a new world object
-func NewWorld(size, chunkSize int) *World {
+func NewWorld(chunkSize int) *World {
 
 	// Try and load the words file
 	var lines []string
@@ -65,23 +64,11 @@ func NewWorld(size, chunkSize int) *World {
 		Rovers:       make(map[string]Rover),
 		CommandQueue: make(map[string]CommandStream),
 		Incoming:     make(map[string]CommandStream),
-		Atlas:        atlas.NewAtlas(size, chunkSize),
+		Atlas:        atlas.NewAtlas(chunkSize),
 		words:        lines,
 	}
 }
 
-// SpawnWorld spawns a border at the edge of the world atlas
-func (w *World) SpawnWorld(fillWorld bool) error {
-	w.worldMutex.Lock()
-	defer w.worldMutex.Unlock()
-	if fillWorld {
-		if err := w.Atlas.SpawnRocks(); err != nil {
-			return err
-		}
-	}
-	return w.Atlas.SpawnWalls()
-}
-
 // SpawnRover adds an rover to the game
 func (w *World) SpawnRover() (string, error) {
 	w.worldMutex.Lock()
@@ -114,16 +101,14 @@ func (w *World) SpawnRover() (string, error) {
 
 	// Seach until we error (run out of world)
 	for {
-		if tile, err := w.Atlas.GetTile(rover.Pos); err != nil {
+		tile := w.Atlas.GetTile(rover.Pos)
-			return "", err
+		if !objects.IsBlocking(tile) {
+			break
 		} else {
-			if !objects.IsBlocking(tile) {
+			// Try and spawn to the east of the blockage
-				break
+			rover.Pos.Add(vector.Vector{X: 1, Y: 0})
-			} else {
-				// Try and spawn to the east of the blockage
-				rover.Pos.Add(vector.Vector{X: 1, Y: 0})
-			}
 		}
+
 	}
 
 	log.Printf("Spawned rover at %+v\n", rover.Pos)
@@ -153,9 +138,7 @@ func (w *World) DestroyRover(rover string) error {
 
 	if i, ok := w.Rovers[rover]; ok {
 		// Clear the tile
-		if err := w.Atlas.SetTile(i.Pos, objects.Empty); err != nil {
+		w.Atlas.SetTile(i.Pos, objects.Empty)
-			return fmt.Errorf("coudln't clear old rover tile: %s", err)
-		}
 		delete(w.Rovers, rover)
 	} else {
 		return fmt.Errorf("no rover matching id")
@@ -213,9 +196,8 @@ func (w *World) WarpRover(rover string, pos vector.Vector) error {
 		}
 
 		// Check the tile is not blocked
-		if tile, err := w.Atlas.GetTile(pos); err != nil {
+		tile := w.Atlas.GetTile(pos)
-			return fmt.Errorf("coudln't get state of destination rover tile: %s", err)
+		if objects.IsBlocking(tile) {
-		} else if objects.IsBlocking(tile) {
 			return fmt.Errorf("can't warp rover to occupied tile, check before warping")
 		}
 
@@ -237,9 +219,8 @@ func (w *World) MoveRover(rover string, b bearing.Bearing) (vector.Vector, error
 		newPos := i.Pos.Added(b.Vector())
 
 		// Get the tile and verify it's empty
-		if tile, err := w.Atlas.GetTile(newPos); err != nil {
+		tile := w.Atlas.GetTile(newPos)
-			return vector.Vector{}, fmt.Errorf("couldn't get tile for new position: %s", err)
+		if !objects.IsBlocking(tile) {
-		} else if !objects.IsBlocking(tile) {
 			// Perform the move
 			i.Pos = newPos
 			w.Rovers[rover] = i
@@ -265,18 +246,12 @@ func (w *World) RoverStash(rover string) (byte, error) {
 	defer w.worldMutex.Unlock()
 
 	if r, ok := w.Rovers[rover]; ok {
-		if tile, err := w.Atlas.GetTile(r.Pos); err != nil {
+		tile := w.Atlas.GetTile(r.Pos)
-			return objects.Empty, err
+		if objects.IsStashable(tile) {
-		} else {
+			r.Inventory = append(r.Inventory, tile)
-			if objects.IsStashable(tile) {
+			w.Rovers[rover] = r
-				r.Inventory = append(r.Inventory, tile)
+			w.Atlas.SetTile(r.Pos, objects.Empty)
-				w.Rovers[rover] = r
+			return tile, nil
-				if err := w.Atlas.SetTile(r.Pos, objects.Empty); err != nil {
-					return objects.Empty, err
-				} else {
-					return tile, nil
-				}
-			}
 		}
 
 	} else {
@@ -306,32 +281,19 @@ func (w *World) RadarFromRover(rover string) ([]byte, error) {
 			Y: roverPos.Y + r.Range,
 		}
 
-		// Make sure we only query within the actual world
-		worldMin, worldMax := w.Atlas.GetWorldExtents()
-		scanMin := vector.Vector{
-			X: maths.Max(radarMin.X, worldMin.X),
-			Y: maths.Max(radarMin.Y, worldMin.Y),
-		}
-		scanMax := vector.Vector{
-			X: maths.Min(radarMax.X, worldMax.X),
-			Y: maths.Min(radarMax.Y, worldMax.Y),
-		}
-
 		// Gather up all tiles within the range
 		var radar = make([]byte, radarSpan*radarSpan)
-		for j := scanMin.Y; j <= scanMax.Y; j++ {
+		for j := radarMin.Y; j <= radarMax.Y; j++ {
-			for i := scanMin.X; i <= scanMax.X; i++ {
+			for i := radarMin.X; i <= radarMax.X; i++ {
 				q := vector.Vector{X: i, Y: j}
 
-				if tile, err := w.Atlas.GetTile(q); err != nil {
+				tile := w.Atlas.GetTile(q)
-					return nil, fmt.Errorf("failed to query tile: %s", err)
+
+				// Get the position relative to the bottom left of the radar
+				relative := q.Added(radarMin.Negated())
+				index := relative.X + relative.Y*radarSpan
+				radar[index] = tile
 
-				} else {
-					// Get the position relative to the bottom left of the radar
-					relative := q.Added(radarMin.Negated())
-					index := relative.X + relative.Y*radarSpan
-					radar[index] = tile
-				}
 			}
 		}
 

pkg/game/world_test.go

@@ -11,14 +11,14 @@ import (
 
 func TestNewWorld(t *testing.T) {
 	// Very basic for now, nothing to verify
-	world := NewWorld(4, 4)
+	world := NewWorld(4)
 	if world == nil {
 		t.Error("Failed to create world")
 	}
 }
 
 func TestWorld_CreateRover(t *testing.T) {
-	world := NewWorld(2, 8)
+	world := NewWorld(8)
 	a, err := world.SpawnRover()
 	assert.NoError(t, err)
 	b, err := world.SpawnRover()
@@ -33,7 +33,7 @@ func TestWorld_CreateRover(t *testing.T) {
 }
 
 func TestWorld_GetRover(t *testing.T) {
-	world := NewWorld(2, 4)
+	world := NewWorld(4)
 	a, err := world.SpawnRover()
 	assert.NoError(t, err)
 
@@ -43,7 +43,7 @@ func TestWorld_GetRover(t *testing.T) {
 }
 
 func TestWorld_DestroyRover(t *testing.T) {
-	world := NewWorld(4, 1)
+	world := NewWorld(1)
 	a, err := world.SpawnRover()
 	assert.NoError(t, err)
 	b, err := world.SpawnRover()
@@ -61,7 +61,7 @@ func TestWorld_DestroyRover(t *testing.T) {
 }
 
 func TestWorld_GetSetMovePosition(t *testing.T) {
-	world := NewWorld(4, 4)
+	world := NewWorld(4)
 	a, err := world.SpawnRover()
 	assert.NoError(t, err)
 
@@ -84,14 +84,14 @@ func TestWorld_GetSetMovePosition(t *testing.T) {
 	assert.Equal(t, pos, newPos, "Failed to correctly move position for rover")
 
 	// Place a tile in front of the rover
-	assert.NoError(t, world.Atlas.SetTile(vector.Vector{X: 0, Y: 2}, objects.LargeRock))
+	world.Atlas.SetTile(vector.Vector{X: 0, Y: 2}, objects.LargeRock)
 	newPos, err = world.MoveRover(a, b)
 	assert.Equal(t, pos, newPos, "Failed to correctly not move position for rover into wall")
 }
 
 func TestWorld_RadarFromRover(t *testing.T) {
 	// Create world that should have visible walls on the radar
-	world := NewWorld(4, 2)
+	world := NewWorld(2)
 	a, err := world.SpawnRover()
 	assert.NoError(t, err)
 	b, err := world.SpawnRover()
@@ -102,40 +102,18 @@ func TestWorld_RadarFromRover(t *testing.T) {
 	assert.NoError(t, world.WarpRover(b, bpos), "Failed to warp rover")
 	assert.NoError(t, world.WarpRover(a, vector.Vector{X: 0, Y: 0}), "Failed to warp rover")
 
-	// Spawn the world wall
-	err = world.Atlas.SpawnWalls()
-	assert.NoError(t, err)
-
 	radar, err := world.RadarFromRover(a)
 	assert.NoError(t, err, "Failed to get radar from rover")
 	fullRange := 4 + 4 + 1
 	assert.Equal(t, fullRange*fullRange, len(radar), "Radar returned wrong length")
 
-	// It should look like:
+	// Test the expected values
-	// ---------
-	// OOOOOOOO-
-	// O------O-
-	// O------O-
-	// O---R--O-
-	// O------O-
-	// O------O-
-	// OR-----O-
-	// OOOOOOOO-
-	PrintTiles(radar)
-
-	// Test all expected values
 	assert.Equal(t, objects.Rover, radar[1+fullRange])
 	assert.Equal(t, objects.Rover, radar[4+4*fullRange])
-	for i := 0; i < 8; i++ {
-		assert.Equal(t, objects.LargeRock, radar[i])
-		assert.Equal(t, objects.LargeRock, radar[i+(7*9)])
-		assert.Equal(t, objects.LargeRock, radar[i*9])
-		assert.Equal(t, objects.LargeRock, radar[(i*9)+7])
-	}
 }
 
 func TestWorld_RoverStash(t *testing.T) {
-	world := NewWorld(2, 2)
+	world := NewWorld(2)
 	a, err := world.SpawnRover()
 	assert.NoError(t, err)
 
@@ -147,15 +125,13 @@ func TestWorld_RoverStash(t *testing.T) {
 	err = world.WarpRover(a, pos)
 	assert.NoError(t, err, "Failed to set position for rover")
 
-	err = world.Atlas.SetTile(pos, objects.SmallRock)
+	world.Atlas.SetTile(pos, objects.SmallRock)
-	assert.NoError(t, err, "Failed to set tile to rock")
 
 	o, err := world.RoverStash(a)
 	assert.NoError(t, err, "Failed to stash")
 	assert.Equal(t, objects.SmallRock, o, "Failed to get correct object")
 
-	tile, err := world.Atlas.GetTile(pos)
+	tile := world.Atlas.GetTile(pos)
-	assert.NoError(t, err, "Failed to get tile")
 	assert.Equal(t, objects.Empty, tile, "Stash failed to remove object from atlas")
 
 	inv, err := world.RoverInventory(a)
@@ -164,7 +140,7 @@ func TestWorld_RoverStash(t *testing.T) {
 }
 
 func TestWorld_RoverDamage(t *testing.T) {
-	world := NewWorld(2, 2)
+	world := NewWorld(2)
 	a, err := world.SpawnRover()
 	assert.NoError(t, err)
 
@@ -179,8 +155,7 @@ func TestWorld_RoverDamage(t *testing.T) {
 	info, err := world.GetRover(a)
 	assert.NoError(t, err, "couldn't get rover info")
 
-	err = world.Atlas.SetTile(vector.Vector{X: 0.0, Y: 1.0}, objects.LargeRock)
+	world.Atlas.SetTile(vector.Vector{X: 0.0, Y: 1.0}, objects.LargeRock)
-	assert.NoError(t, err, "Failed to set tile to rock")
 
 	vec, err := world.MoveRover(a, bearing.North)
 	assert.NoError(t, err, "Failed to move rover")
@@ -192,7 +167,7 @@ func TestWorld_RoverDamage(t *testing.T) {
 }
 
 func TestWorld_RoverRepair(t *testing.T) {
-	world := NewWorld(2, 2)
+	world := NewWorld(2)
 	a, err := world.SpawnRover()
 	assert.NoError(t, err)
 
@@ -207,15 +182,13 @@ func TestWorld_RoverRepair(t *testing.T) {
 	originalInfo, err := world.GetRover(a)
 	assert.NoError(t, err, "couldn't get rover info")
 
-	err = world.Atlas.SetTile(pos, objects.SmallRock)
+	world.Atlas.SetTile(pos, objects.SmallRock)
-	assert.NoError(t, err, "Failed to set tile to rock")
 
 	o, err := world.RoverStash(a)
 	assert.NoError(t, err, "Failed to stash")
 	assert.Equal(t, objects.SmallRock, o, "Failed to get correct object")
 
-	err = world.Atlas.SetTile(vector.Vector{X: 0.0, Y: 1.0}, objects.LargeRock)
+	world.Atlas.SetTile(vector.Vector{X: 0.0, Y: 1.0}, objects.LargeRock)
-	assert.NoError(t, err, "Failed to set tile to rock")
 
 	vec, err := world.MoveRover(a, bearing.North)
 	assert.NoError(t, err, "Failed to move rover")